Best golf resource that has improved your game?

What is the best golf book, video, website or resource you have ever used?

A personal coach?

Lessons?

Books, videos, DVDS?

Whatcha got?

For me (this is Marc), lessons was the big bang for me, coupled with a few pro tips and a lot of time at the range. Now, granted, that got me from shooting in the 110’s to the mid 90’s. Still that’s like 10-15 strokes in about a year. I’m sure if I had played more I would have even done better. I’d be curious to hear more about what you have used? Perhaps Golf is Hard TV episodes have helped?